Respiratory mask filter



FIG. 1 is a front elevation view of the invention;

FIG. 2 is a rear elevation view of the invention;

FIG. 3 is a left elevation view of the invention;

FIG. 4 is a right elevation view of the invention;

FIG. 5 is a top plan view of the invention;

FIG. 6 is bottom plan view of the invention; and,

FIG. 7 is a perspective view of the invention.

The broken lines illustrate portions of the respiratory mask filterwhich form no part of the claimed, design.

CLAIM The ornamental design for a respiratory mask filter, as shown anddescribed.